fpc/compiler/regvars.pas
2000-12-25 00:07:25 +00:00

583 lines
22 KiB
ObjectPascal

{
$Id$
Copyright (c) 1998-2000 by Florian Klaempfl and Jonas Maebe
This unit handles register variable allocation
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
****************************************************************************
}
unit regvars;
{$i defines.inc}
interface
uses
aasm,
node,
symsym,
cpubase;
procedure assign_regvars(p: tnode);
procedure load_regvars(asml: TAAsmoutput; p: tnode);
procedure cleanup_regvars(asml: TAAsmoutput);
{$ifdef i386}
procedure store_regvar(asml: TAAsmoutput; reg: tregister);
procedure load_regvar(asml: TAAsmoutput; vsym: pvarsym);
procedure load_regvar_reg(asml: TAAsmoutput; reg: tregister);
procedure load_all_regvars(asml: TAAsmoutput);
{$endif i386}
implementation
uses
globtype,systems,comphook,
cutils,cobjects,verbose,globals,
symconst,symbase,symtype,symdef,types,
hcodegen,cpuasm,tgcpu;
var
parasym : boolean;
procedure searchregvars(p : pnamedindexobject);
var
i,j,k : longint;
begin
if (psym(p)^.typ=varsym) and (vo_regable in pvarsym(p)^.varoptions) then
begin
j:=pvarsym(p)^.refs;
{ parameter get a less value }
if parasym then
begin
if cs_littlesize in aktglobalswitches then
dec(j,1)
else
dec(j,100);
end;
{ walk through all momentary register variables }
for i:=1 to maxvarregs do
begin
with pregvarinfo(aktprocsym^.definition^.regvarinfo)^ do
if ((regvars[i]=nil) or (j>regvars_refs[i])) and (j>0) then
begin
for k:=maxvarregs-1 downto i do
begin
regvars[k+1]:=regvars[k];
regvars_para[k+1]:=regvars_para[k];
regvars_refs[k+1]:=regvars_refs[k];
end;
{ calc the new refs
pvarsym(p)^.refs:=j; }
regvars[i]:=pvarsym(p);
regvars_para[i]:=parasym;
regvars_refs[i]:=j;
break;
end;
end;
end;
end;
procedure searchfpuregvars(p : pnamedindexobject);
var
i,j,k : longint;
begin
if (psym(p)^.typ=varsym) and (vo_fpuregable in pvarsym(p)^.varoptions) then
begin
j:=pvarsym(p)^.refs;
{ parameter get a less value }
if parasym then
begin
if cs_littlesize in aktglobalswitches then
dec(j,1)
else
dec(j,100);
end;
{ walk through all momentary register variables }
for i:=1 to maxfpuvarregs do
begin
with pregvarinfo(aktprocsym^.definition^.regvarinfo)^ do
if ((fpuregvars[i]=nil) or (j>fpuregvars_refs[i])) and (j>0) then
begin
for k:=maxfpuvarregs-1 downto i do
begin
fpuregvars[k+1]:=fpuregvars[k];
fpuregvars_para[k+1]:=fpuregvars_para[k];
fpuregvars_refs[k+1]:=fpuregvars_refs[k];
end;
{ calc the new refs
pvarsym(p)^.refs:=j; }
fpuregvars[i]:=pvarsym(p);
fpuregvars_para[i]:=parasym;
fpuregvars_refs[i]:=j;
break;
end;
end;
end;
end;
{$ifdef i386}
function reg32(reg: tregister): tregister;
begin
case regsize(reg) of
S_B: reg32 := reg8toreg32(reg);
S_W: reg32 := reg16toreg32(reg);
S_L: reg32 := reg;
end;
end;
{$else i386}
function reg32(reg: tregister): tregister;
begin
reg32 := reg;
end;
{$endif i386}
procedure assign_regvars(p: tnode);
{ register variables }
var
regvarinfo: pregvarinfo;
i: longint;
begin
{ max. optimizations }
{ only if no asm is used }
{ and no try statement }
if (cs_regalloc in aktglobalswitches) and
((procinfo^.flags and (pi_uses_asm or pi_uses_exceptions))=0) then
begin
new(regvarinfo);
fillchar(regvarinfo^,sizeof(regvarinfo^),0);
aktprocsym^.definition^.regvarinfo := regvarinfo;
if (p.registers32<4) then
begin
parasym:=false;
symtablestack^.foreach({$ifdef FPCPROCVAR}@{$endif}searchregvars);
{ copy parameter into a register ? }
parasym:=true;
symtablestack^.next^.foreach({$ifdef FPCPROCVAR}@{$endif}searchregvars);
{ hold needed registers free }
for i:=maxvarregs downto maxvarregs-p.registers32+1 do
begin
regvarinfo^.regvars[i]:=nil;
regvarinfo^.regvars_para[i] := false;
end;
{ now assign register }
for i:=1 to maxvarregs-p.registers32 do
begin
if assigned(regvarinfo^.regvars[i]) and
(reg_pushes[varregs[i]] < regvarinfo^.regvars[i]^.refs) then
begin
{ register is no longer available for }
{ expressions }
{ search the register which is the most }
{ unused }
usableregs:=usableregs-[varregs[i]];
is_reg_var[varregs[i]]:=true;
dec(c_usableregs);
{ possibly no 32 bit register are needed }
{ call by reference/const ? }
if (regvarinfo^.regvars[i]^.varspez in [vs_var,vs_out]) or
((regvarinfo^.regvars[i]^.varspez=vs_const) and
push_addr_param(regvarinfo^.regvars[i]^.vartype.def)) then
begin
regvarinfo^.regvars[i]^.reg:=varregs[i];
end
else
if (regvarinfo^.regvars[i]^.vartype.def^.deftype in [orddef,enumdef]) and
(porddef(regvarinfo^.regvars[i]^.vartype.def)^.size=1) then
begin
{$ifdef i386}
regvarinfo^.regvars[i]^.reg:=reg32toreg8(varregs[i]);
{$endif}
end
else
if (regvarinfo^.regvars[i]^.vartype.def^.deftype in [orddef,enumdef]) and
(porddef(regvarinfo^.regvars[i]^.vartype.def)^.size=2) then
begin
{$ifdef i386}
regvarinfo^.regvars[i]^.reg:=reg32toreg16(varregs[i]);
{$endif}
end
else
begin
regvarinfo^.regvars[i]^.reg:=varregs[i];
end;
if regvarinfo^.regvars_para[i] then
unused:=unused - [regvarinfo^.regvars[i]^.reg];
{ procedure uses this register }
{$ifdef i386}
usedinproc:=usedinproc or ($80 shr byte(varregs[i]));
{$endif i386}
{$ifdef m68k}
usedinproc:=usedinproc or ($800 shr word(varregs[i]));
{$endif m68k}
end
else
begin
regvarinfo^.regvars[i] := nil;
regvarinfo^.regvars_para[i] := false;
end;
end;
end;
if ((p.registersfpu+1)<maxfpuvarregs) then
begin
parasym:=false;
symtablestack^.foreach({$ifdef FPCPROCVAR}@{$endif}searchfpuregvars);
{$ifdef dummy}
{ copy parameter into a register ? }
parasym:=true;
symtablestack^.next^.foreach({$ifdef FPCPROCVAR}@{$endif}searchregvars);
{$endif dummy}
{ hold needed registers free }
{ in non leaf procedures we must be very careful }
{ with assigning registers }
if aktmaxfpuregisters=-1 then
begin
if (procinfo^.flags and pi_do_call)<>0 then
begin
for i:=maxfpuvarregs downto 2 do
regvarinfo^.fpuregvars[i]:=nil;
end
else
begin
for i:=maxfpuvarregs downto maxfpuvarregs-p.registersfpu do
regvarinfo^.fpuregvars[i]:=nil;
end;
end
else
begin
for i:=aktmaxfpuregisters+1 to maxfpuvarregs do
regvarinfo^.fpuregvars[i]:=nil;
end;
{ now assign register }
for i:=1 to maxfpuvarregs do
begin
if assigned(regvarinfo^.fpuregvars[i]) then
begin
{$ifdef i386}
{ reserve place on the FPU stack }
regvarinfo^.fpuregvars[i]^.reg:=correct_fpuregister(R_ST0,i-1);
{$endif i386}
{$ifdef m68k}
regvarinfo^.fpuregvars[i]^.reg:=fpuvarregs[i];
{$endif m68k}
end;
end;
end;
end;
end;
{$ifdef i386}
procedure store_regvar(asml: TAAsmoutput; reg: tregister);
var
i: longint;
hr: preference;
regvarinfo: pregvarinfo;
vsym: pvarsym;
begin
regvarinfo := pregvarinfo(aktprocsym^.definition^.regvarinfo);
if not assigned(regvarinfo) then
exit;
for i := 1 to maxvarregs do
if assigned(regvarinfo^.regvars[i]) and
(reg32(regvarinfo^.regvars[i]^.reg) = reg) then
begin
if regvar_loaded[reg32(reg)] then
begin
vsym := pvarsym(regvarinfo^.regvars[i]);
new(hr);
reset_reference(hr^);
if vsym^.owner^.symtabletype in [inlinelocalsymtable,localsymtable] then
hr^.offset:=-vsym^.address+vsym^.owner^.address_fixup
else hr^.offset:=vsym^.address+vsym^.owner^.address_fixup;
hr^.base:=procinfo^.framepointer;
asml.concat(Taicpu.op_reg_ref(A_MOV,regsize(vsym^.reg),vsym^.reg,hr));
asml.concat(Tairegalloc.dealloc(reg32(reg)));
regvar_loaded[reg32(reg)] := false;
end;
break;
end;
end;
procedure load_regvar(asml: TAAsmoutput; vsym: pvarsym);
var
hr: preference;
opsize: topsize;
opcode: tasmop;
begin
if not regvar_loaded[reg32(vsym^.reg)] then
begin
asml.concat(Tairegalloc.alloc(reg32(vsym^.reg)));
{ zero the regvars because the upper 48bits must be clear }
{ for 8bits vars when using them with btrl }
{ don't care about sign extension, since the upper 24/16 }
{ bits won't be adapted when doing maths anyway (JM) }
case regsize(vsym^.reg) of
S_L:
begin
opsize := S_L;
opcode := A_MOV;
end;
S_W:
begin
opsize := S_WL;
opcode := A_MOVZX;
end;
S_B:
begin
opsize := S_BL;
opcode := A_MOVZX;
end;
end;
asml.concat(Tairegalloc.alloc(reg32(vsym^.reg)));
new(hr);
reset_reference(hr^);
if vsym^.owner^.symtabletype in [inlinelocalsymtable,localsymtable] then
hr^.offset:=-vsym^.address+vsym^.owner^.address_fixup
else hr^.offset:=vsym^.address+vsym^.owner^.address_fixup;
hr^.base:=procinfo^.framepointer;
asml.concat(Taicpu.op_ref_reg(opcode,opsize,hr,reg32(vsym^.reg)));
regvar_loaded[reg32(vsym^.reg)] := true;
end;
end;
procedure load_regvar_reg(asml: TAAsmoutput; reg: tregister);
var
i: longint;
regvarinfo: pregvarinfo;
begin
regvarinfo := pregvarinfo(aktprocsym^.definition^.regvarinfo);
if not assigned(regvarinfo) then
exit;
reg := reg32(reg);
for i := 1 to maxvarregs do
if assigned(regvarinfo^.regvars[i]) and
(reg32(regvarinfo^.regvars[i]^.reg) = reg) then
load_regvar(asml,pvarsym(regvarinfo^.regvars[i]))
end;
procedure load_all_regvars(asml: TAAsmoutput);
var
i: longint;
regvarinfo: pregvarinfo;
begin
regvarinfo := pregvarinfo(aktprocsym^.definition^.regvarinfo);
if not assigned(regvarinfo) then
exit;
for i := 1 to maxvarregs do
if assigned(regvarinfo^.regvars[i]) and
(reg32(regvarinfo^.regvars[i]^.reg) in [R_EAX,R_EBX,R_ECX,R_EDX]) then
load_regvar(asml,pvarsym(regvarinfo^.regvars[i]))
end;
{$endif i386}
procedure load_regvars(asml: TAAsmoutput; p: tnode);
var
i: longint;
{hr : preference;}
regvarinfo: pregvarinfo;
begin
if (cs_regalloc in aktglobalswitches) and
((procinfo^.flags and (pi_uses_asm or pi_uses_exceptions))=0) then
begin
regvarinfo := pregvarinfo(aktprocsym^.definition^.regvarinfo);
{ can happen when inlining assembler procedures (JM) }
if not assigned(regvarinfo) then
exit;
{$ifdef m68k}
for i:=1 to maxvarregs do
begin
{ parameter must be load }
if regvarinfo^.regvars_para[i] then
begin
{ procinfo is there actual, }
{ because we can't never be in a }
{ nested procedure }
{ when loading parameter to reg }
new(hr);
reset_reference(hr^);
hr^.offset:=pvarsym(regvarinfo^.regvars[i])^.address+procinfo^.para_offset;
hr^.base:=procinfo^.framepointer;
asml.concat(Taicpu,op_ref_reg(A_MOVE,regsize(regvarinfo^.regvars[i]^.reg),
hr,regvarinfo^.regvars[i]^.reg)));
end
end;
{$endif m68k}
for i:=1 to maxvarregs do
begin
if assigned(regvarinfo^.regvars[i]) then
begin
if cs_asm_source in aktglobalswitches then
asml.insert(Tai_asm_comment.Create(strpnew(regvarinfo^.regvars[i]^.name+
' with weight '+tostr(regvarinfo^.regvars[i]^.refs)+' assigned to register '+
reg2str(regvarinfo^.regvars[i]^.reg))));
if (status.verbosity and v_debug)=v_debug then
Message3(cg_d_register_weight,reg2str(regvarinfo^.regvars[i]^.reg),
tostr(regvarinfo^.regvars[i]^.refs),regvarinfo^.regvars[i]^.name);
end;
end;
for i:=1 to maxfpuvarregs do
begin
if assigned(regvarinfo^.fpuregvars[i]) then
begin
{$ifdef i386}
{ reserve place on the FPU stack }
regvarinfo^.fpuregvars[i]^.reg:=correct_fpuregister(R_ST0,i-1);
asml.concat(Taicpu.op_none(A_FLDZ,S_NO));
{$endif i386}
{$ifdef dummy}
{ parameter must be load }
if regvarinfo^.fpuregvars_para[i] then
begin
{ procinfo is there actual, }
{ because we can't never be in a }
{ nested procedure }
{ when loading parameter to reg }
new(hr);
reset_reference(hr^);
hr^.offset:=pvarsym(regvarinfo^.regvars[i])^.address+procinfo^.para_offset;
hr^.base:=procinfo^.framepointer;
{$ifdef i386}
asml.concat(Taicpu,op_ref_reg(A_MOV,regsize(regvarinfo^.regvars[i]^.reg),
hr,regvarinfo^.regvars[i]^.reg)));
{$endif i386}
{$ifdef m68k}
asml.concat(Taicpu,op_ref_reg(A_MOVE,regsize(regvarinfo^.regvars[i]^.reg),
hr,regvarinfo^.regvars[i]^.reg)));
{$endif m68k}
end;
{$endif dummy}
end;
end;
if assigned(p) then
if cs_asm_source in aktglobalswitches then
asml.insert(Tai_asm_comment.Create(strpnew(tostr(p.registersfpu)+
' registers on FPU stack used by temp. expressions')));
for i:=1 to maxfpuvarregs do
begin
if assigned(regvarinfo^.fpuregvars[i]) then
begin
if cs_asm_source in aktglobalswitches then
asml.insert(Tai_asm_comment.Create(strpnew(regvarinfo^.fpuregvars[i]^.name+
' with weight '+tostr(regvarinfo^.fpuregvars[i]^.refs)+' assigned to register '+
reg2str(regvarinfo^.fpuregvars[i]^.reg))));
if (status.verbosity and v_debug)=v_debug then
Message3(cg_d_register_weight,reg2str(regvarinfo^.fpuregvars[i]^.reg),
tostr(regvarinfo^.fpuregvars[i]^.refs),regvarinfo^.fpuregvars[i]^.name);
end;
end;
if cs_asm_source in aktglobalswitches then
asml.insert(Tai_asm_comment.Create(strpnew('Register variable assignment:')));
end;
end;
procedure cleanup_regvars(asml: TAAsmoutput);
var
i: longint;
begin
{$ifdef i386}
{ can happen when inlining assembler procedures (JM) }
if not assigned(aktprocsym^.definition^.regvarinfo) then
exit;
if (cs_regalloc in aktglobalswitches) and
((procinfo^.flags and (pi_uses_asm or pi_uses_exceptions))=0) then
with pregvarinfo(aktprocsym^.definition^.regvarinfo)^ do
begin
for i:=1 to maxfpuvarregs do
if assigned(fpuregvars[i]) then
{ ... and clean it up }
asml.concat(Taicpu.op_reg(A_FSTP,S_NO,R_ST0));
for i := 1 to maxvarregs do
if assigned(regvars[i]) and
(regvar_loaded[reg32(regvars[i]^.reg)]) then
asml.concat(Tairegalloc.dealloc(reg32(regvars[i]^.reg)));
end;
{$endif i386}
end;
end.
{
$Log$
Revision 1.15 2000-12-25 00:07:28 peter
+ new tlinkedlist class (merge of old tstringqueue,tcontainer and
tlinkedlist objects)
Revision 1.14 2000/12/05 11:44:32 jonas
+ new integer regvar handling, should be much more efficient
Revision 1.13 2000/11/29 00:30:39 florian
* unused units removed from uses clause
* some changes for widestrings
Revision 1.12 2000/11/04 14:25:21 florian
+ merged Attila's changes for interfaces, not tested yet
Revision 1.11 2000/10/31 22:02:51 peter
* symtable splitted, no real code changes
Revision 1.10 2000/10/14 10:14:52 peter
* moehrendorf oct 2000 rewrite
Revision 1.9 2000/10/01 19:48:25 peter
* lot of compile updates for cg11
Revision 1.8 2000/09/30 16:08:45 peter
* more cg11 updates
Revision 1.7 2000/09/30 13:08:16 jonas
* regvars are now zeroed at the start of their life if they contain an 8
or 16bit var/parameter, because the full 32bits are used if they are
necessary for a btrl instruction
Revision 1.6 2000/09/24 15:06:27 peter
* use defines.inc
Revision 1.5 2000/08/27 16:11:52 peter
* moved some util functions from globals,cobjects to cutils
* splitted files into finput,fmodule
Revision 1.4 2000/08/17 11:07:51 jonas
* fixed crash when inlining assembler procedures with -Or
Revision 1.3 2000/08/04 05:52:00 jonas
* correct version (I also had a regvars.pp locally, which was used
instead of the regvars.pas on CVS, so I didn't notice the errors :( )
Revision 1.2 2000/08/03 14:36:47 jonas
* fixed inserting of allocated register for regvars (only those for
parameters were done, and sometimes even the wrong ones)
Revision 1.1 2000/08/03 13:17:25 jonas
+ allow regvars to be used inside inlined procs, which required the
following changes:
+ load regvars in genentrycode/free them in genexitcode (cgai386)
* moved all regvar related code to new regvars unit
+ added pregvarinfo type to hcodegen
+ added regvarinfo field to tprocinfo (symdef/symdefh)
* deallocate the regvars of the caller in secondprocinline before
inlining the called procedure and reallocate them afterwards
}